Seals

Non-contact seals

Bearings with non-contact seals can be operated at the same speeds as bearings with shields, but with improved sealing effectiveness. The seals form an extremely narrow gap with the inner ring shoulder and are available in two different designs.

Seals made of oil and wear-resistant NBR that is reinforced by a sheet steel insert are identified by the designation suffix RZ (fig. 1).

The seals made of PTFE are fixed in the outer ring by a retaining ring (fig. 2). Bearings with seals made of PTFE (designation suffix TS) are available on request.

Low-friction seals

Low-friction seals made of PTFE (designation suffix TS) are fixed in the outer ring by a retaining ring and are practically non-contacting with a recess in the inner ring shoulder (fig. 3). Bearings with seals made of PTFE (designation suffix TS) are available on request.

Contact seals

Contact seals are made of oil and wear-resistant NBR or FKM and are reinforced with a sheet steel insert.

As standard the bearings are equipped seals made of NBR (designation suffix RS1), which seal against the inner ring shoulder (fig. 4) or against a recess in the inner ring (fig. 5). The exact seal design may differ from the illustrations.

Bearings with designation suffix VP311 are equipped with seals made of food compatible, blue-coloured NBR. The material is FDA and EC approved. FDA approval is according to CFR 21 section 177.2600 'Rubber articles intended for repeated use' for use in contact with aqueous and fatty foods. EC approval is according to the overall migration requirements of the German BfR recommendation XXI for category 3 materials.

Bearings with seals made of FKM (designation suffix RS2) are available on request.

WARNING

Seals made of PTFE (polytetrafluoroethylene) or FKM (fluoro rubber) exposed to an open flame or temperatures above 300 °C (570 °F) are a health and environmental hazard! They remain dangerous even after they have cooled.